Intercepting pressing the HOME and the power button?

Question

Android

It is necessary to make an application that cannot be closed without knowing the password. Those. no pressing Home, power button, etc. should not close the application. You need to do it in order to issue devices to stupid users and be sure that they do not log out.
So, in order to protect against any blockers, as far as I understand, this cannot be done in stock firmware.
Question: where to dig to solve the problem? root, custom firmware - anything, if only the task was solved.

Answer 1

why not? The android api allows you to intercept buttons at the level of a running activity. developer.android.com/reference/android/text/method/KeyListener.html

Answer 2

If you want to restrict users so that they can only use 1 program. you need to somehow remove the default shell and all default applications from the device and replace it with this program.

Answer 3

There is some info here.